MerCruiser Complete Driveshaft / Gear Housing Assembly
R/MR/Alpha One
| Aftermarket | MerCruiser OEM | Ratio |
| - | 5-5010130CP | 1.30 (16/20) |
| SE-10601 | 5-5010147CP | 1.47 (20/22) |
| SE-10602 | 5-5010162CP | 1.62 (24/24) |
| SE-10603 | 5-5010181CP | 1.81 (17/19) |
| SE-10604 | 5-5010194CP | 1.94 (20/24) |
NOTE: When using the Alpha One Sterndrive Assembly as a replacement on earlier (pre 1983) 4 & 6 cylinder inline models, it will be necessary to replace the standard yoke with a short U‑joint yoke. This yoke is not included and must be removed from the old unit.
The in-line number 1 drive before the R(redesigned), MR(mercruiser redesigned), and Alpha drives have a short splinded yoke 8 1/8 in (20.6cm) and the newer R, MR, and Alpha have a longer splined yoke of 9 9/16 (24.3cm). They will not interchange, as yoke and coupler damage will result.
